"What if all software was open source? Anybody would then be able to add custom features to Microsoft Word, Adobe Photoshop, Apple iTunes or any other program. A University of Washington project may make this possible." Yeah I know, odd headline - couldn't find anything better.

From what I recall reading, it almost became law that all software would need its source code registered for copyright protection. This was from before the US went to automatically granted copyright protection.

If the US had gone that other way, all source code would be available from the Library of Congress for anyone to read. That wouldn't make it "Open Source" for modification and redistribution but it would have been readable.